7. Cashews

Cashews are a tropical plant that produces an apple-like fruit and a nut that grows out of each fruit. The apple, which starts out yellow and becomes red when ripe, is edible and high in vitamin C, but it’s reportedly not that tasty. Each fruit produces only one nut. If you’ve noticed that you can’t buy unshelled cashews, there’s a reason: the shells are toxic — they contain the same chemical as poison ivy and can cause rashes.

18. Pistachios

The pistachio tree is a desert plant that grows fruit in clusters. When the shells are ripe, they change from green to yellow and split open, revealing the nut. The coolest part? That split often happens with an audible pop.